Display strings using a typing and a ticker effect. Typing effect can also be used to capture input.

typer-example.py

import typer as t

def main(stdscr):

    string = "Hello World!"
    # Simple typing of a string
    t.label(string)
    # String on same line (default)
    # Delay (ms) can be adjusted to your liking (default is 40ms)
    t.label(string, delay=20, nl=0)
    t.label(string, delay=60, nl=0)
    # String on new line
    t.label(string, on_nl=1)
    t.endwin()
    string = t.prompt("Enter string here: ", delay=50)
    # label and ticker can be made to pause
    t.ticker(string, delay=40, pause=0)
    # iters governs the number of characters that are skipped over in the string
    # Useful for very long strings
    t.ticker(string, pause=1, iters=3)
    t.endwin()

t.wrapper(main)

# A longer string - 1234567890

typer.py

# Change log
# v1.1.1 - clean up for publication | 29/12
#   v1.1 - added ticker() | 23/12
#     v1 - where the dream began | 19-23/12

from curses import curs_set, newwin, endwin, getsyx, setsyx, raw, noraw, napms, echo, wrapper

# Set delay in ms, default is 40
delay = 40

# Type output onto terminal in a typewriter fashion
# Basically complete, is_prompt functionality missing
# delay: delay in ms, pause
def label(my_string=str, pause = 1, nl = 1, on_nl=0, delay=40):
    # Set cursor invisible
    curs_set(0)
    raw()

    # Basic error catching
    try:
        from curses import getsyx
    except ModuleNotFoundError:
        print("curses not installed. Use command `pip install curses` to install.")
        return(1)
    if my_string == '':
        raise ValueError("[0x01] - String emtpy.")
    if pause < 0 or pause > 1:
        raise ValueError("[0x02] - 'pause' parameter bad value.")
    if nl < 0 or nl > 1:
        raise ValueError("[0x03] - 'nl' parameter bad value.")
    if on_nl < 0 or on_nl > 1:
        raise ValueError("[0x04] - 'on_nl' parameter bad value.")

    # Initialise variables
    i, y, x, b_y, b_x = 0, 0, 0, 0, 0
    # Get current y and x positions
    b_y = getsyx()[0]
    b_x = getsyx()[1]

    # Add new line at start of line if on_nl is set to 1
    if on_nl == 1:
        b_y += 1
        b_x = 0

     # Initialise text box
    text_window = newwin(y, x, b_y, b_x)

    # <output>
    while i < len(my_string):
        text_window.addch(my_string[i])
        i += 1
        napms(delay)
        text_window.refresh()
    # </output>

    # Add a pause
    if pause == 1:
        text_window.getkey()
    # Add new line at the end of output if flag nl is 1
    if nl == 1:
        setsyx(b_y + 1, 0)

    # Reset screen
    curs_set(1)
    noraw()

# Function marquees input text, captures input as string and returns string
def prompt(my_string=str, delay=40, on_nl=0):
    # Clear screen, set cursor invisible, set echo to true
    # curs_set(0)
    echo(True)
    noraw()

    # Initialise variables
    i, y = 0, 0
    input_string = ""
    input_char = ''

    # Initialise text box, on new line if needed
    if on_nl == 1:
            y = getsyx()[0]

    text_window = newwin(0, 0, y, 0)

    # Replicating label function, as textboxes are function level objects and are destroyed afterwards
    try:
        while i < len(my_string):
            text_window.addch(my_string[i])
            i += 1
            napms(delay)
            text_window.refresh()
    except:
        my_string = None

    # Keep adding characters to string until Enter is pressed
    while True:
        input_char = text_window.get_wch()

        if input_char == '\n':
            break

        input_string += str(input_char)
        y, x = text_window.getyx()
        text_window.addstr(y, x, '')
        text_window.refresh()

    setsyx(getsyx()[0], 0)

    # Return input_string
    return(input_string)

    # Reset screen
    curs_set(1)
    echo(False)

def ticker(my_string=str, pause=1, delay=20, iters=1, nl=1):
    # Initialisation as per usual
    curs_set(0)

    x = 0
    text_window = newwin(0, 0, getsyx()[0], 0)

    # Kludge to fix a bug I can't nail. If pause=0 and iters>1, the last
    # character of my_string not print correctly.
    if pause == 0:
        iters = 1
    # This loop iterates over each character in string in place, then repeats the same for each character in string
    while x < len(my_string):
        for r in range(len(my_string)):
            # iters governs how many character are skipped over during iteration
            text_window.addch(0, x, my_string[r//iters])
            napms(delay)
            text_window.refresh()
            # This exact placement ensures the printed character is the right one
            text_window.addch(0, x, my_string[x])
        # Continue while loop
        x += 1

    # Standard stuff
    if pause == 1:
        text_window.getch()

    if nl == 1:
        setsyx(getsyx()[0] + 1, 0)
    elif nl == 0:
        setsyx(getsyx()[0], len(my_string))

    curs_set(1)

1_edit.mp4

TYPER.py

• Display string using a typing effect | .label(pause, nl, on_nl, delay)

  • Can also return str output | .prompt(delay, on_nl)

• Can also utilise a ticker effect | .ticker(pause, delay, iters, nl)

• Minimal necessary functions imported from curses

• All functions have adjustable delay, nl (new line) parameters

See typer-example.py for example

Bug list:

• Weird bug where the last character is not printed correctly by .ticker(), if pause=0 and iters>1
  Current workaround: force iters=1 when pause=0 ^{(kludgy I know)}

Constructive criticism welcome but please remember this is my first project 🙂